Re: Need different rod for streamers?
Here are my thoughts. I would lose the 8' of sinking line. Some people use them and like them but as you found out there are a bear to cast. If you have to use one cut it down to 3 or 4 feet.
I would much prefer:
1. A floating line with a weighted fly.
2. A floating line with an indicator, 9' leader and split shot just above the tippet.
3. A floating line with a sinking leader and a weighted fly. This would be a good application for a furled leader with some sink-it worked into the furled leader. You would need a short furled leader with a tippet added. You can buy sinking furled leaders. I have not tried this combination.
4. A floating line with an integrated sink tip with a short leader.
5. An integrated shooting head line like the Teeny #130 with a short leader.
I think any of these options would be a better combination than your 8' add on sink tip. With 1, 2 or 3 you can use your floating line. With the rest you will need a second spool for your reel and a new fly line. Your add on sink tip can be used for still water fishing.
In regards to your fly rod. The RIO Grand fly line is 1/2 line heavier than a standard 5wt fly line. Then you are adding 8' of add on sink tip. I don't think this is a good combination for a mid-flex rod. You need to change your setup or I think a heavier or faster rod would be better.